Factors affecting durm wheat grain color.

RONCALLO, P.F.; AKKIRAJU P; CARRERA, A.; HELGUERA, M.; CERVIGNI, G.; MIRANDA R; JENSEN C; VIVIANA ECHENIQUE

Rosario, Argentina

Conferencia; 1 Conferencia latinoamericana ICC 2007; 2007

Asoc. Internacional de Qcos, Cerealistas

The bright yellow colour of durum wheat grain and products is due to the presence of carotenoid pigments of the xanthophylls type, mainly lutein, and their enzymatic degradation, where a major role appear to be played by the lipoxygenase-linoleate system over other enzymes like peroxidases and polyphenol oxidases. Colour is an important quality trait in pasta wheat. The aim of this work was the characterization of the more common Argentinean pasta wheat varieties according to its carotenoid pigment content, using different biochemical methods and their association with the yellow colour index (b value). Field trails were conducted in three locations using 8 varieties from Argentina and two from US, using a complete randomized block design with 3 replicates (N=90). Whole meal samples were obtained with a cyclonic mill. Each sample was evaluated for carotenoid pigment content (lutein and ß-carotene) using the standard AACC 14-50 method and the microtest described by Fares et al.(1991; Molini d?Italia, Anno XLII 12:19-21), the yellow index using reflectance spectrophotometry (CIE L*a*b*) and the thousand-kernel-weight. The ß-carotene content ranged from  4,61 to 13,03 p.p.m. The analysis of variance showed that the pigment content, measured by both methods, and the yellow index were affected by the genotype (p